Manufacture of iron.



PATENTED AUG. 14, 1906.

0.. THIEL.

MAN UPAGTURE OF IRON.

APPLICATION FILED APR.28. 1906.

, onic" THIEL, or TLANDSTUHL, GERMANY;

MANUFACTURE OF IRON.

To rill whom it may concern: 7 Be it known that I, OTTO THIEL, a subjectof the German Emperor, and a resident of Landstuhl, Rhenish Palatinate,Empire of @Germany, have invented a cer'tain'new and useful Improvementin and Relating to the Manufacture of Iron, of which the following is aspecification.

This invention relates to a recess for ob t'aining iron directly from sag containing oxid of iron.

Accordin to the improved process a slag bath is protTuced overanexisting liquid-iron bath from iron ore, iron slag, burned pyrites, &c.,in an apparatus Which'is capable of always. maintaining the slag andiron in a liquid-state. By the introduction of carbon or substancescontaining carbon in large roportionsuch as, for instance, coke, antacite, &c.into the slag containing iron oxid the iron separated andprecipitated. is at once absorbed by the liquid iron bath under it.

Many years ago attempts were made to melt iron with fluxes and toseparate the iron from the slag so obtained by means of carbon withoutmaking use of the blast-furnace. In an experiment made for this purposein a reverberatory furnace it has been, in fact, found possible toproduce iron in the sha e of ingots surrounded by liquid slag, whic ingots could be made into bar-iron or placed in liquid cast-iron. Thatprocess for obtaining iron directly from the ore has, however, re mainedpractically unsuccessful, for a slag rich in iron has resulted, thereremaining too' much iron in the slag. The reduced iron in the shape ofan ingot became oxidized in the open air, whereby losses were caused.The necessary subse uent treatment was of course combined with t 1eWell-known drawbacks of the manufacture of welded iron.

A complete or nearly complete reduction of iron from a liquid slagcontaining oxid of iron can be effected in a regular and economicalmanner only when it is possible to maintain the iron and sla in li uidstate before, during, and after t e reduction. In the above-mentionedexperiments, however, the iron and slag'were not obtained in hot liquidstate, and they could not reach that state at all. It would have beendisadvantageous to maintain the iron liquid, as during the action of theflame a large portion of iron would have been-again oxidized. However,in the new process according to this invention the iron and slag aremaintained in liquidstate Specification of Letters Patent.

Application filed April 28,1906; Serial No 314.183.

Patented Aug. 1a, 1906.

' before, during, and after the reduction, the

liquid iron-containing slag being prepared over aliquiddron bath; Thereduction of the iron-containing slag then takes place over ahot'liquid-iron bath, all oxidation thus being {avoided This iron-bathat the same time maintains the slag in a liquid state by its'excess ofheat, so that only very little outside and auxiliary heating isrequired. Owing to the whole mass of the slag being ,maintained liquidthe action of the carbon, and

consequently the reduction, becomes perfect.

Whether iron ore and lime are converted directly on the iron-bath into aslag or Whether in a separate apparatus and the molten slag then pouredout onto the iron-bath is immaterial. The consumption of. heat requiredby the reduction of the liquid slag containing oxid of iron is coveredby the excess of heat stored up in the iron-bath. Heat can also besupplied at any moment by firing the furnace in which the iron iscontained. The

iron separated is taken. up directly by the iron-bath, so that any lossthrough oxidation, &c is avoided.

The process itself can be carried out in. any apparatus which isarranged in such manner that it produces the temperature required formaintaining iron and slag in a liquid state. The reduction of the slagis best effected by anthracite, coke, or the like. The reducing materialis introduced into the slag in the manner suitable for each individualcase that is to say, from the top, from the side, &c.

A practical method of carrying out the new process will now be describedand reference made to the accompanying drawings, showing in Figures 1and 2 a tipping furnace in diagrammatic cross-section in two workingpositions. i

Let us assume a tipping furnace of one hundred tons capacity, containingsixty tons of liquid iron. 7 On the top of it are melted twenty tons ofslag containing oxid of iron, (iron ore with fluxas, for instance,lime.) The openings 0, Fig. 1, of the furnace are then properly closedwith insertions E, the

holes 1 2 3 of which are made similar to the air-holes in the bottom ofconverters. The furnace is thereupon tipped over, Fig. 2, the

; slag flows over the insertions, and at the same moment the reducingmaterial (coke-powder, anthracite, &c.) is introduced into the slagthrough the holes 1 2 3 in the insertions E, if necessary, underpressure. When a large quantity of coke is introduced, the furnace istipped backward, Fig 1, whereby a good mixing of the slag with the cokeis produced. A violent reduction takes place and can be increased byagitation. Then the furnace is tippedover again, Fig. 2, and fresh cokeis introduced, and so on until a sample taken of the slag shows thatonly a very little iron remains in it. The sla poor in iron and a partof the iron are pour-e off, the iron being sub-' sequently treatedaccording to requirements, while on the top of the iron remaining in thefurnace afr'esh twenty tons of ore and lime are converted into slag andreduced in the above-mentioned manner;

The supply of carbon can, of course, be effected in various Ways. Thus,for instance, carbon-containing materials could be mixed with hot tar,so as to form a thin fluid aste, which is then pumpedinto the liquislag. This would be a similar process to that used in workingconverters.

' The reducingsubstance can also be easily introduced through suitablelateral widening of the furnace and a good mixing obtained. The reducingmaterial is preferably used in a hot state, if possible. It can also bemixed with a small quantity of pulverized ore.

The oxid of carbon produced during the reaction can be utilized in thefurnace ltself or 30 conveyed away and used for other urposes.

What I claim as my invention, an desire to secure by Letters Patent, is-

1. In the manufacture of iron, forming a slag layer containing oxid ofiron upon the surface of'an iron-bath, maintaining the slag and iron ina liquid state and reducing the iron from the slag by means of areducing material whereupon the reduced iron 18 directly absorbed by theiron-bath.

2. In the manufacture of iron applying a molten slag layer containingoxid of iron upon the surface of an iron-bath, maintaining the slag andiron in a liquid state and reducing the iron from the slag by means of areduclng material whereupon the reduced iron is directly absorbed by theiron-bath.

3. In the manufacture of iron, forming a slag layer containing oxid ofiron upon the surface of an iron-bath, maintaining the slag and iron ina liquid state, and reducing the iron from the slag by injectingreducing material into the molten slag, whereupon the geduced iron isdirectly absorbed by the ironath.

4. In the manufacture of iron forming a slag layer containing oxid ofiron upon the surface of an iron-bath maintaining the slag and iron in aliquid state and reducin the ironfrom the sla by blowing in pow credreducing materizfi into the molten slag,

,whereu on the reduced iron is directly absorbed y the iron-bath.

In testimony whereof I have signed my name to this specification in thepresence of twosubscribing witnesses.

OTTO THIEL.

Witnesses:

' H. W. HARRIS, Jos. H. LEUTE

